Wireless communications comprises cellular and non-cellular wireless communications. Cellular technologies include wideband code division multiple access, WCDMA, and global system for mobile communication, GSM, technologies, for example. Non-cellular technologies include WiFi, also known as 802.1x, and ad-hoc communications, for example. In the context of non-cellular communications, mobile devices may be provisioned with addresses such as internet protocol, IP, addresses for use in communication with further nodes, for example by using a 802.1x radio access point as a way to reach the internet.
Mobile devices may be furnished with connectivity via both cellular and non-cellular technologies, which the mobile device may be configured to use depending on various parameters, such as a quality-of-service requirement of a data flow or a price of a connection. Cellular systems employ handover mechanisms that are designed to provide a seamless mobility experience to users, while non-cellular systems may have more attractive pricing or offer a higher datarate, for example.
As a mobile device moves, it may change its attachment from a first to a second access point responsive to determining that the second access point offers a more favourable radio path. In conjunction with the change in attachment, continuity of communication may need to be ensured, including continuity of IP-based communication, for example. Where coordination between the first and second access points is lacking, for example when they belong to different non-cellular networks, the mobile device can perform an initial access procedure to obtain connectivity through the second access point to replace connectivity through the first access point. When a mobile device powers on from an unpowered state, it needs to be provisioned with an address to participate in address-based communication.
IP based addressing occurs in two primary variants, internet protocol version 4 known as IPv4 and internet protocol version 6 known as IPv6.